Alpine ski

ABSTRACT

An alpine ski including a body, front and rear tips, a running surface overlaid by at least one lower reinforcement layer, a core and at least one upper reinforcement layer. The core has a central member made of a hard material which extends over a portion of the length and width of the ski, and an edge made of a softer material that borders the core member on the sides, front and rear.

BACKGROUND OF THE INVENTION

[0001] 1. Field of the Invention

[0002] The present invention relates to an alpine ski.

[0003] 2. Description of Background and Relevant Information

[0004] In a known fashion, a ski is in the form of an elongated beam having a running, or gliding, surface on its bottom, and receiving on its upper surface retaining elements, i.e., bindings, that are provided to retain the skier's boot.

[0005] The pressure distribution of the ski on its gliding surface is an important parameter that determines gliding and turning qualities of the ski.

[0006] Numerous solutions aiming at better controlling this pressure distribution have been proposed.

[0007] Among these solutions, the one described in the Patent Application EP 938 917 proposes to mount the retaining elements on two oscillating plates connected to the ski by transverse journal axles which extend through the structure of the ski. The plates are connected to one another by a linkage.

[0008] Such a construction yields good results. However, it is rather adapted to skis that are relatively narrow in the skid area, i.e., the central portion of the ski.

SUMMARY OF THE INVENTION

[0009] An object of the invention is to propose a construction for facilitating the control of pressure distribution best suited for wide skis.

[0010] The ski according to the invention includes an elongated body, front and rear tips, a running surface overlaid by at least one lower reinforcement layer, a core and at least one upper reinforcement layer. The core of the ski of the invention has a central member, made of a hard material, which extends over a portion of the length and width of the ski, and an edge made of a softer material that borders with the core member on the sides, front and rear.

[0011] According to a secondary characteristic of the invention, the central member projects height-wise in relation to the remainder of the core.

[0012] According to another secondary characteristic, the ski is overlaid by two oscillating plates having an upper mounting surface provided to receive retaining elements, the plates being assembled to the ski about a transverse axle borne by the member of the core.

BRIEF DESCRIPTION OF DRAWINGS

[0013] The invention will be better understood from the description that follows, with reference to the annexed drawings, in which:

[0014]FIG. 1 is a perspective view of a bare ski according to the present invention.

[0015]FIG. 2 is a cross-sectional view of the ski of FIG. 1 in the area of its central zone.

[0016]FIG. 3 is a cross-sectional view of the ski of FIG. 1 toward one of its tips.

[0017]FIG. 4 shows the member of the core.

[0018]FIG. 5 shows the central zone of the ski of FIG. 1 equipped with plates.

[0019]FIG. 6 is a transverse cross-sectional view of the ski in the area of one of its plates.

DETAILED DESCRIPTION OF THE INVENTION

[0020] The ski 1 shown in FIG. 1 includes an elongated body 2, with two front and rear tips 3 and 4. The front tip 3 is turned up and rounded so as to form a shovel. In the embodiment shown, the rear tip 4 is also turned up and rounded. However, this is not limiting, and one could have an end formed in a straight line, or a substantially straight line, as for a conventional ski.

[0021] In a known fashion, the ski 1 has a running surface 6 in its lower portion. The running surface is laterally bordered with two lateral running edges 7 and 8.

[0022] The running surface 6 is overlaid by a reinforcement layer 9 made of fiber-reinforced resin, which is itself overlaid preferably by a metallic reinforcement layer made, in particular, of aluminum. These various layers are housed between the running edges 7 and 8.

[0023] Above this lower sub-assembly is located the core 12, described in greater detail below. Preferably, a metallic reinforcement layer 14, of the same type as the layer 10, is located above the core. If the layer 10 is present, so is the layer 14, in principle. Finally, an upper reinforcement layer 16, made of resin reinforced with a fiber lap, covers the assembly in the manner of a shell, i.e., this layer descends along the lateral sides until overlying the lateral running edges. Preferably, as shown in FIGS. 3 and 4, the running edges 7, 8 overlap on each side over a small width, and the upper reinforcement layer 16 descends until contacting these overlapping portions which it covers.

[0024] Conventionally, an adhesive film is inserted between the metallic reinforcement layers, if they are present, and the core. These layers are not shown in the figures of the drawing. Moreover, the upper reinforcement layer is covered with a decorating layer that is also not shown in the drawing. This decorating layer can be of any appropriate and known type.

[0025] According to the invention, the core 12 includes two main portions of different types. Initially, the core 12 has an intermediate member 18 made out of a relatively hard material, such as wood. More particularly, the intermediate member is a central member. The central member 18 extends over only a portion of the length and width of the ski.

[0026] According to the embodiment shown, the central member 18 of the core rests height-wise on the lower sub-assembly, i.e., on the metallic reinforcement layer 10; and it projects upwardly in relation to the remainder of the core. Thus, in FIG. 1, the projecting member 19 is formed by the central core member 18 covered by the upper reinforcement layers. In the central portion of the ski, the projecting member 19 is relatively wide. Its width is close to that of a conventional ski, or approximately 60 millimeters. This value is not limiting.

[0027]FIG. 4 shows a perspective view of the central member 18 of the core. It is formed, for example, by an elongated wooden block. The block is thinned width-wise toward each of its ends 18 a and 18 b. In these zones, its thickness is also reduced by machining its upper portion. In its median portion 21, the central member 18 of the core has lateral edges and substantially parallel upper and lower surfaces.

[0028] As described above, the core member 18 is preferably made of wood, for example, of glued beech or poplar slats, and it is shaped by machining.

[0029] The remainder of the core, which laterally forms the edge 22 of the member 18 on the front and rear, is made of a softer and lighter material than the member 18. For example, the sides are possibly made of glass fiber reinforced polyurethane foam. This edge is made, for example, of a cake of foam cut and machined to the desired shape, with a central cutout in which the core member 18 is housed.

[0030] The central core member 18 and the edge 22 define two zones of the ski with a clearly distinct height. To take this into account, the metallic reinforcement layer 14, if present, is preferably formed of two portions, one edge portion 14 a which covers the edge of the core, and which has a central cutout through which the member 18 extends, and a central portion 14 b which covers the upper surface of the central member 18 of the core by conforming to its shape.

[0031] The cross-section of the ski shown in FIG. 2 is obtained in the central zone, where the member 18 and the edge 22 of the core are positioned side-by-side. The cross-section view of FIG. 3 is obtained toward either of the ends where the core 12 is formed solely by the edge 22.

[0032] A ski according to this embodiment has been made with the following dimensions: a length of 1950 millimeters, maximum width of 120 millimeters at the shovel, minimum width of 86 millimeters in the central zone, maximum width of 115 millimeters at the tail, with a core having a member 1200 millimeters long, 60 millimeters wide, projecting by 8 millimeters toward the center and 1.5 millimeters toward the ends in relation to the remainder of the core, the ski being 12 millimeters thick in these edge zones. These dimensions are provided by way of example only and do not limiting the breadth of the invention.

[0033] To support the elements for retaining the boot, the ski of the invention is preferably equipped with two plates 23 and 24. The plates have the same construction, with an upper mounting surface 23 a, 24 a, which is provided to be bored and to receive front and rear retaining elements of a known type. The mounting surfaces 23 a and 24 a are maintained slightly raised with respect to the upper surface of the ski.

[0034] The plates 23, 24 straddle the projecting member 19 of the ski. They are each formed, for example, by an aluminum plate or the like, which is bent to the width of the member 19 so as to form two lateral wings which descend along the sides of the projecting member 19.

[0035] Thus, the plate 23 which is shown in cross-section in FIG. 6 has two lateral wings 23 b, 23 c which extend along the projecting member 19.

[0036] Each of the wings 23 b, 23 c is bored with an opening through which a screw extends, the screw being threaded within the core member. The screws for assembling a plate are screwed in alignment with one another, so as to define, for the plate, a transverse oscillation axis which extends through the member of the core. In an alternative embodiment, instead of screws, one could have a pin, for example, that extends through the structure of the ski. One could also use inserts housed in the structure of the ski during manufacture.

[0037] To enable the passage of the screw heads during mounting, the ski preferably has in the edge zone of the edge four shallow transverse grooves 26, 27, 28, 29 which are in alignment with the housings of the screws. The depth of the grooves is determined so as to enable the passage of the screw heads. Moreover, against the projecting member 19, the ski has a small recess in the area of each of the screw housings for housing the wing of the plate. The recesses 34 and 35 for the wings 23 b and 23 c are shown in FIG. 6. These various reliefs of the ski are formed by cutting or machining the core, or by another appropriate means. Preferably, the metallic reinforcement layer 14 is shaped so as to conform to the shape of these reliefs.

[0038] Above the projecting member 19, thin pads 30, 31, 32, 33 made of a deformable material, such as elastomer, for example, are inserted between the mounting surfaces of the plates and the upper surface of the projecting member. The pads can be made of a different hardness; in this case, the inner pads 31 and 32 are preferably harder than the outer pads 30 and 33. The pads fill the space between the plates and the ski.

[0039] As the ski is being used, the two-part core enables a better distribution of the pressures. Indeed, the wooden core member stiffens the central portion of the ski where the largest portion of the pressure is concentrated. It acts like a beam that spreads over its entire length the support forces of the boot that are concentrated in the area of the connections between the plates and the ski. As a result, the peaks of pressure which are usually encountered toward each connection or each retaining element are attenuated. Moreover, the oscillating plates that carry the elements for retaining the boot release the ski in bending and ensure a better winding of the ski in turns, resulting in a better steering of the ski. The portion of the core that is made of foam provides the ski with lightness and a certain flexibility. In this way, it is possible to construct skis that are very wide, in particular in the central zone. These skis have a high bearing capacity, in view of their gliding surface. Nevertheless, they are very easy to handle due to the particular construction of the core and to the journalled plates.

[0040] The present description is provided for guidance only, and other embodiments of the invention could be adopted without leaving the scope thereof.

[0041] In particular, the member of the core made of a hard material could occupy only a portion of the thickness of the core. On the other portion of its thickness, the core could be formed by the same material as the projecting member, in particular polyurethane foam.

[0042] In this case, the central member 18 of the core would not be in direct contact with the lower sub-assembly of the ski, but would however maintain its function of distributing pressure over the gliding surface.

[0043] Also, one could implement another method of mounting the retaining elements. For example, the elements could be assembled directly on top of the projecting member 19, taking advantage of its width. In these conditions, the difference in height between the top of the projecting member and the remainder of the ski could be reduced. As a borderline case, the core member and the projecting member could have substantially the same thickness.

[0044] The instant application is based upon the French Patent Application No. 00 06175, filed May 10, 2000, the disclosure of which is hereby incorporated by reference thereto in its entirety, and the priority of which is hereby claimed under 35 U.S.C. §119. 

What is claimed is:
 1. An alpine ski comprising: a longitudinally elongated body, a front tip, a rear tip, a lower running surface, two lateral running edges bordering said running surface; at least one lower reinforcement layer positioned above said running surface; a core positioned above said lower reinforcement layer; at least one upper reinforcement layer positioned above said core; said core comprising: a central member made of a relatively hard material, said central member extending over at least a portion of the length and width of the ski; and an edge made of a material softer than said relatively hard material, said edge bordering said central member on lateral sides, front, and rear of said central member.
 2. A ski according to claim 1 , wherein: said central member of said core projects upwardly with respect to said edge, so as to form a projecting member from an upper surface of the ski.
 3. A ski according to claim 2 , wherein: said central member of said core projects by about 1.5 to about 8 millimeters with respect to said edge.
 4. A ski according to claim 1 , wherein: said central member is made of wood and said edge of said core is made of fiber-reinforced polyurethane foam.
 5. A ski according to claim 1 , wherein: said running edges include a laterally overlapping portion, and said upper reinforcement layer extends downwardly along lateral sides of the ski until reaching said running edges, said upper reinforcement layer covering said overlapping portion of said running edges.
 6. A ski according to claim 1 , wherein: said central member of said core extends between said upper and lower reinforcement layers.
 7. A ski according to claim 1 , wherein: said central member of said core extends over only a portion of a height of said core defined between said upper and lower reinforcement layers.
 8. A ski according to claim 2 , further comprising: two plates overlying the ski, each of said two plates having a mounting surface provided for a binding for a boot, each of said two plates further comprising two lateral wings extending along sides of said projecting member, said mounting surfaces of said plates being located above an upper surface of said projecting member, and said mounting plates being mounted for oscillation about a transverse axis extending through said central member of said core.
 9. A ski according to claim 8 , wherein: each of said plates is assembled to the ski by screws screwed into said central member of said core.
 10. A ski according to claim 8 , wherein: pads made of an elastically deformable material are positioned between each of said plates and said upper surface of said projecting member.
 11. A ski according to claim 8 , wherein: said ski has a length of about 1950 millimeters, a width of about 86 millimeters or more in a central zone, and said central member of said core having a length of about 1200 millimeters and a width of about 80 millimeters at a central part. 